Field of the Invention
[0001] The present invention relates to the olefin polymerization field, in particular to
a use of organosilane in preparation of an in-reactor polyolefin alloy, a method of
preparing an in-reactor polyolefin alloy, and an in-reactor polyolefin alloy prepared
by the method.
Background of the Invention
[0002] A polyolefin blending technique is a technique of directly melting and blending compatible
homopolymer/homopolymer, homopolymer/copolymer, or copolymer/copolymer to product
a polymer alloy. An in-reactor polyolefin alloy is a polyolefin alloy obtained directly
from reacting monomers through in-reactor polymerization. That method replaces the
traditional blending method that melts and blends polymer components in the prior
art. Among in-reactor polyolefin alloys, the most common in-reactor polyolefin alloy
is in-reactor polypropylene alloy, which is usually produced by forming propylene
into porous polypropylene particles through polymerization in the presence of a olefin
polymerization catalyst and then charging a comonomer of ethylene and α-olefin into
the polymerization system to perform a copolymerization reaction in the porous polypropylene
particles so that the elastic copolymer generated fills up the voids among the porous
polypropylene particles.
[0003] In recent years, though the olefin polymerization modifiers that have new structures
and new features have been discovered and applied in researches for improving the
performance of in-reactor polyolefin alloys continuously, effective catalytic polymerization
means for preparing some high-performance in-reactor polyolefin alloys that have wide
application prospects are still inadequate. For example, polypropylene-based thermoplastic
elastomers (Thermoplastic Dyamic Vulcanizate, TPV) in which the rubber phase is in
a crosslinked structure have outstanding mechanical properties and high added values,
and have wide application prospects in high-end application domains. However, the
existing TPV products are mainly obtained through modification processes after polymerization
(dynamic vulcanization and crosslinking). There is no report on preparation of TPV
through a polymerization process.
[0004] Making the rubber phase crosslinked through polymerization has advantages in many
aspects: 1.) a complex post-modification process is omitted, and the increased cost
incurred by the process is eliminated; 2.) the in-reactor crosslinking technique has
characteristics including controllable degree of crosslinking and more diversified
products, and thereby a series of in-reactor polyolefin alloys, such as in-reactor
polyolefin alloys with high rubber content (rubber mass percent is 50 mass% or higher),
high impact-resistant in-reactor polyolefin alloys, and polypropylene-based thermoplastic
elastomers (TPV) which rubber phase is in a crosslinked structure, etc., can be prepared
in a controlled manner by adjusting the kind of crosslinking monomer and addition
amount; 3) the dependency on the polymerization catalyst and the polymerization process
is lower.
Content of the Invention
[0005] The present invention is to provide a use of organosilane in preparation of an in-reactor
polyolefin alloy, a method of preparing an in-reactor polyolefin alloy, and an in-reactor
polyolefin alloy prepared by the method.
[0006] Specifically, the present invention provides a use of organosilane in preparation
of an in-reactor polyolefin alloy, wherein the organosilane is represented by a general
formula R
1mSiX
n(OR
2)
k, wherein R
1 is a C
2-C
20 alkyl group and a terminal of R
1 has an α-olefin double bond, a norbornene group, a cycloolefin group or a dicyclopentadiene
group, X is a halogen element, R
2 is a C
1-C
20 linear chain, branched chain or isomerized alkyl group, m is an integer within a
range of 1-3, n is an integer within a range of 1-3, k is an integer within a range
of 0-2, and m+n+k=4.
[0007] The present invention further provides a method of preparing an in-reactor polyolefin
alloy comprising: conducting the first polymerization reaction of the first olefin
monomer in the presence of a catalyst, and then charging the second olefin monomer
into the polymerization reaction system to perform the second polymerization reaction,
wherein the first olefin monomer is different from the second olefin monomer, wherein
the first polymerization reaction and/ or the second polymerization reaction are/is
executed in the presence of organosilane represented by a general formula R
1mSiX
n(OR
2)
k, wherein R
1 is a C
2-C
20 alkyl group and a terminal of R
1 has an α-olefin double bond, a norbornene group, a cycloolefin group or a dicyclopentadiene
group, X is a halogen element, R
2 is a C
1-C
20 linear chain, branched chain or isomerized alkyl group, m is an integer within a
range of 1-3, n is an integer within a range of 1-3, k is an integer within a range
of 0-2, and m+n+k=4.
[0008] Furthermore, the present invention further provides an in-reactor polyolefin alloy
obtained by the above-mentioned method.
[0009] Through in-depth research, the inventor of the present invention has found that the
organosilane represented by the general formula R
1mSiX
n(OR
2)
k behaves quite differently from the organosilane represented by a general formula
Si(OR')
4 (wherein R' is a C
1-C
20 alkyl group) and the organohalosilane represented by a general formula SiX'
4 (wherein X' is a halogen element) during the in-reactor polyolefin alloy preparation
process. If the first and/or the second polymerization reaction in the in-reactor
polyolefin alloy preparation process are executed in the presence of the organosilane
represented by the general formula R
1mSiX
n(OR
2)
k, the degree of crosslinking of the rubber phase in the obtained in-reactor polyolefin
alloy is higher, and the in-reactor polyolefin alloy has higher impact toughness and
lower tensile breaking strength.
[0010] According to the preferred example of the present invention, if the R
1 in the organosilane is a C
2-C
20 alkyl group and a terminal of R
1 has an α-double bond, a norbornene group, a cycloolefin group or a dicyclopentadiene
group, X is a halogen element, R
2 is a C
1-C
10 linear chain, branched chain or isomerized alkyl group, m is 2 or 3, n is 1 or 2,
k is 0, and m+n+k=4, the rubber phase in the obtained in-reactor polyolefin alloy
is crosslinked to a higher degree, and the in-reactor polyolefin alloy has higher
impact strength and lower tensile breaking strength.
[0011] Other features and advantages of the present invention will be further detailed in
the examples hereunder.
Detailed Description of the Examples
[0012] Hereunder some examples of the present invention will be detailed. It should be understood
that the examples described here are only provided to describe and explain the present
invention, but shall not be deemed as constituting any limitation to the present invention.
[0013] The present invention provides a use of organosilane in preparation of an in-reactor
polyolefin alloy, wherein the organosilane is represented by a general formula R
1mSiX
n(OR
2)
k, wherein a plurality of R
1 is the same general formula may be the same with or different from each other, and
may be a C
2-C
20 alkyl group respectively and independently, and a terminal of R
1 has an α-olefin double bond, a norbornene group, a cycloolefin group or a dicyclopentadiene
group; a plurality of X in the same general formula may be the same with or different
from each other, and may be a halogen element (including fluorine, chlorine, bromine,
iodine) respectively and independently; a plurality of R
2 in the same general formula may be the same with or different from each other, and
may be a C
1-C
20 linear chain, branched chain or isomerized alkyl group respectively and independently;
m is an integer with a range of 1-3, n is an integer within a range of 1-3, k is an
integer within a range of 0-2, and m+n+k=4.
[0014] According to the present invention, preferably, a plurality of R
1 in the same general formula may be the same with or different from each other, and
is a C
2-C
20 alkyl group respectively and independently, and a terminal of R
1 has an α-olefin double bond, a norbornene group, a cycloolefin group or a dicyclopentadiene
group; a plurality of X in the same general formula may be the same with or different
from each other, and is a halogen element (including fluorine, chlorine, bromine,
iodine) respectively and independently; a plurality of R
2 in the same general formula may be the same with or different from each other, and
is a C
1-C10 linear chain, branched chain or isomerized alkyl group respectively and independently;
m is 2 or 3, n is 1 or 2, k is 0, and m+n+k=4. When the preferred organosilane is
used as a modifier to prepare an in-reactor polyolefin alloy, the degree of crosslinking
of the rubber phase in the obtained in-reactor polyolefin alloy can be further improved,
the impact toughness of the in-reactor polyolefin alloy can be further improved, and
the tensile breaking strength of the in-reactor polyolefin alloy can be further decreased.
[0015] In the case that a terminal of R
1 has an α-olefin double bond (CH
2=CH-), there is no particular restriction on the structure of the middle part of R
1 except for the α-olefin double bond; specifically, the middle part may include linear
chain alkyl (including double bonds and triple bonds, etc.) or its isomers. In that
case, examples of the organosilane include, but are not limited to at least one of
7-octenyl trichlorosilane, 5-hexenyl trichlorosilane, allyl trichlorosilane, di-(7-octenyl)
dichlorosilane, di-(allyl) dichlorosilane, 7-octenyl allyl dichlorosilane, 7-octenyl
vinyl dichlorosilane, 5-hexenyl allyl dichlorosilane, 7-octenyl di-(allyl) chlorosilane,
di-(7-octenyl) allyl chlorosilane, and triallyl chlorosilane, etc.
[0016] In the case that the terminal of R
1 has a norbornene group, preferably the structure of R
1 is represented by the following Formula (1):
[0017] Wherein, the group bonded to silicon atom may be R
3, R
4, or R
5, and R
3, R
4 and R
5 are H or C
1-C
10 alkyl (including alkenyl, alkynyl, or cycloalkenyl, etc.) respectively and independently,
but are not limited to specific structures, including linear chain alkyl or its isomers.
For example, if R
1 has the structure represented by Formula (1), R
3 is H, R
4 is =CH-CH
3, R
5 is ethylidene and is bonded to the silicon atom, m=2, n=2, k=0, and X is Cl, the
organosilane is 2-(5-ethylidene-2-norbornene) ethyl allyl dichlorosilane; if R
1 has the structure represented by Formula (1), R
3 is H, R
4 is ethylidene and is bonded to the silicon atom, R
5 is ethyl, m=2, n=2, k=0, and X is Cl, the organosilane is di-[2-(5-ethylidene-2-norbornene)
ethyl] dichlorosilane.
[0018] If a terminal of R
1 has a cycloolefin group, the carbon number of the cycloolefin group may be 3-10,
the number of double bonds in the cycloolefin group may be 1-3, the carbon number
of the alkyl chain that connects the cycloolefin group with the silicon atom may be
1-10, and the alkyl includes linear chain alkyl or its isomers. Furthermore, the ring
of the cycloolefin group may have a branch chain, which preferably is C
1-C
5 alkyl. In that case, examples of the organosilane include, but are not limited to
at least one of 2-(3-cyclohexenyl) ethyl trichlorosilane, 4-(2,7-cyclooctadiene) butyl
trichlorosilane, 2-[2-(3-cyclohexenyl)ethyl)] dichlorosilane, 2-(dicyclopentadiene)
ethylidene allyl dichlorosilane, and 2-(dicyclopentadiene) ethylidene trichlorosilane.
[0019] In the case that a terminal of R
1 has a dicyclopentadiene group, preferably the structure of R
1 is represented by the following Formula (2):
[0020] Wherein, the group bonded to silicon atom may be R
6, R
7, or R
8, and R
6, R
7 and R
8 are H or C
1-C
10 alkyl respectively and independently, but are not limited to specific structures,
including linear chain alkyl or its isomers. For example, if R
1 has the structure represented by Formula (2), R
6 is H, R
7 is H, R
8 is 1,2-ethylidene and is bonded to silicon atom, m=2, n=2, k=0, and X is Cl, the
organosilane is 2-(dicyclopentadiene) ethylidene allyl dichlorosilane; if R
1 has the structure represented by Formula (2), R
6 and R
7 are H, R
8 is ethylidene and is bonded to silicon atom, m=2, n=2, k=0, and X is Cl, the organosilane
is di-[2-(dicyclopentadiene) ethylidene] dichlorosilane.
[0021] As described above, the examples of the organosilane include, but are not limited
to at least one of 7-octenyl trichlorosilane, 5-hexenyl trichlorosilane, allyl trichlorosilane,
di-(7-octenyl) dichlorosilane, di-(allyl) dichlorosilane, 7-octenyl allyl dichlorosilane,
7-octenyl vinyl dichlorosilane, 5-hexenyl allyl dichlorosilane, 7-octenyl di-(allyl)
chlorosilane, di-(7-octenyl) allyl chlorosilane, triallyl chlorosilane, 2-(5-ethylidene-2-norbornene)
ethyl allyl dichlorosilane, di-[2-(5-ethylidene-2-norbornene) ethyl] dichlorosilane,
2-(5-ethylidene-2-norbornene)-ethyl allyl dichlorosilane, 2-(5-ethylidene-2-norbornene)
ethyl trichlorosilane, 2-(3-cyclohexenyl) ethyl trichlorosilane, 4-(2,7-cyclooctadiene)
butyl trichlorosilane, di-[2-(3-cyclohexenyl) ethyl)]dichlorosilane, 2-(dicyclopentadiene)
ethylidene allyl dichlorosilane, 2-(dicyclopentadiene) ethylidene trichlorosilane,
2-(dicyclopentadiene) ethylidene allyl dichlorosilane, and di-[2-(dicyclopentadiene)
ethylidene] dichlorosilane, preferably is at least one of 7-octenyl allyl dichlorosilane,
7-octenyl vinyl dichlorosilane, 5-hexenyl allyl dichlorosilane, 7-octenyl di-(allyl)
chlorosilane, di-(7-octenyl) allyl chlorosilane, di-(7-octenyl) dichlorosilane, triallyl
chlorosilane, di-(allyl) dichlorosilane, 2-(5-ethylidene-2-norbornene) ethyl allyl
dichlorosilane, di-[2-(5-ethylidene-2-norbornene) ethyl] dichlorosilane, di-[2-(3-cyclohexenyl)
ethyl] dichlorosilane, 2-(dicyclopentadiene) ethylidene allyl dichlorosilane, and
di-[2-(dicyclopentadiene) ethylidene] dichlorosilane. When the preferred organosilane
is used as a modifier to prepare an in-reactor polyolefin alloy, the degree of crosslinking
of the rubber phase in the obtained in-reactor polyolefin alloy can be further improved,
the impact toughness of the in-reactor polyolefin alloy can be further improved, and
the tensile breaking strength of the in-reactor polyolefin alloy can be further decreased.
[0022] The present invention provides a method of preparing an in-reactor polyolefin alloy
comprising: conducting the first polymerization reaction of the first olefin monomer
in the presence of a catalyst, and then charging the second olefin monomer into the
polymerization reaction system to perform the second polymerization reaction, wherein
the first olefin monomer is different from the second olefin monomer, the first polymerization
reaction and/or the second polymerization reaction are/is executed in the presence
of organosilane represented by a general formula R
1mSiX
n(OR
2)
k, wherein R
1 is a C
2-C
20 alkyl group and the terminal of R
1 has an α-olefin double bond, a norbornene group, a cycloolefin group or a dicyclopentadiene
group, X is a halogen element, R
2 is a C
1-C
20 linear chain, branched chain or isomerized alkyl group, m is an integer within a
range of 1-3, n is an integer within a range of 1-3, k is an integer within a range
of 0-2, and m+n+k=4.
[0023] Moreover, the specific selections of the organosilane have been described above,
and will not be further detailed here.
[0024] There is no particular restriction on the dose of the organosilane in the present
invention. Preferably, in relation to 100pbw total dose of the first olefin monomer
and the second olefin monomer, the total dose of the organosilane is 0.0001-20pbw,
further preferably is 0.0001-5pbw, more preferably is 0.0005-1pbw, optimally is 0.001-0.5pbw.
Thus, the impact toughness of the obtained in-reactor polyolefin alloy can be further
improved, and the tensile breaking strength of the in-reactor polyolefin alloy can
be further decreased.
[0025] According to the method of preparing an in-reactor polyolefin alloy provided in the
present invention, the first polymerization reaction may be executed in the presence
of the organosilane, or the second polymerization reaction may be executed in the
presence of the organosilane; alternatively, both the first polymerization reaction
and the second polymerization reaction may be executed in the presence of the organosilane.
According to a preferred example of the present invention, the first polymerization
reaction is executed without the presence of the organosilane, while the second polymerization
reaction is executed in the presence of the organosilane, so as to ensure that the
polymer obtained through the second polymerization reaction has a crosslinked structure
or branched structure.
[0026] A main improvement in the method of preparing an in-reactor polyolefin alloy provided
in the present invention lies in that the organosilane represented by the general
formula R
1mSiX
n(OR
2)
k is added in the preparation process of the in-reactor polyolefin alloy, while the
kinds of the first olefin monomer, the second olefin monomer and the catalyst and
the conditions of the first polymerization reaction and the second polymerization
reaction may be conventional choices in the art.
[0027] For example, both the first olefin monomer and the second olefin monomer may be monomers
that can have an olefin polymerization reaction in the prior art. Specifically, the
olefin monomers may be ethylene and/or α-olefin. Wherein, the α-olefin may be any
mono-olefin with double bonds at the terminal of the molecular chain. For example,
the α-olefin may be at least one of propylene, 1-butylene, 1-pentene, 1-hexylene,
and 1-octylene. Particularly preferably, the first olefin monomer is propylene, and
the second olefin monomer is a mixture of ethylene and α-olefin; in that case, the
obtained in-reactor polyolefin alloy is an in-reactor polypropylene alloy. In that
case, in the second polymerization reaction process, based on the total weight of
the ethylene and the α-olefin, the dose of the ethylene may be 1-99wt.%, preferably
is 20-50wt.%; the dose of the α-olefin may be 1-99wt.%, preferably is 50-80wt.%. The
weight ratio of the dose of the propylene in the first polymerization reaction process
to the total does of the ethylene and the α-olefin in the second polymerization reaction
process may be 0.2-100:1, preferably is 0.5-10:1. Furthermore, it should be noted:
the first olefin monomer is different from the second olefin monomer, which means
the kind of the first olefin monomer is not the same as the kind of the second olefin
monomer fully, i.e., the first olefin monomer may be different from the second olefin
monomer fully or partially.
[0028] The catalyst may be any substance that can be used to catalyze the olefin monomer
to have a polymerization reaction in the prior art. Examples of the catalyst include,
but are not limited to at least one of Ziegler-Natta catalyst, metallocene catalyst,
and non-metallocene catalyst. Wherein, the specific compositions of those catalysts
are well known to those skilled in the art. For example, the Ziegler-Natta catalyst
may be an MgCl
2 supported catalyst system or VOCl
3-AlEt
2Cl catalyst system, etc. Specifically, the MgCl
2 supported catalyst system usually contains MgCl
2, TiCl
4, alkyl aluminum and/or alkoxy aluminum, and optional internal electron donor and/or
external electron donor. The specific composition is well known to those skilled in
the art, and will not be detailed further here.
[0029] There is no particular restriction on the conditions of the first polymerization
reaction and the second polymerization reaction in the present invention. For example,
the conditions of the first polymerization reaction usually include: reaction temperature
in the range of 30-90°C, preferably 40-80°C, more preferably 60-75°C; reaction time
in the range of 0.05-10h, preferably 0.1-2h, more preferably 0.1-0.5h. Furthermore,
if the first olefin monomer charged in the first polymerization reaction is in a gas
state, the conditions of the first polymerization reaction further include: reaction
pressure in the range of 0-40atm, preferably 1-35atm, more preferably 5-10atm. The
conditions of the second polymerization reaction usually include: reaction temperature
in the range of 60-120°C, preferably 75-95 °C, more preferably 80-90 °C; reaction
time in the range of 0.1-10h, preferably 0.1-2h, more preferably 0.2-0.5h. Furthermore,
if the second olefin monomer charged in the second polymerization reaction is in a
gas state, the conditions of the second polymerization reaction further include: reaction
pressure in the range of 0.1-15atm, preferably 0.2-10atm, more preferably 4-6atm.
In the present invention, the pressure value refers to gauge pressures. Furthermore,
the first polymerization reaction and/or the second polymerization reaction preferably
are executed in the presence of hydrogen. In the first polymerization reaction, in
relation to 100pbw first olefin monomer, the dose of the hydrogen may be 0.001-0.5pbw,
preferably is 0.005-0.1pbw; in the second polymerization reaction, in relation to
100pbw second olefin monomer, the dose of the hydrogen may be 0.001-5pbw, preferably
is 0.02-0.15pbw.
[0030] According to the method of preparing an in-reactor polyolefin alloy provided in the
present invention, preferably the method further comprises: washing the product obtained
by the second olefin polymerization reaction with water and/or alcohol at 20-120°C
after the second olefin polymerization reaction is finished, so that the degree of
branching or crosslinking of the in-reactor polyolefin alloy can be further improved,
and thereby the impact toughness of the in-reactor polyolefin alloy can be further
improved. Wherein, the alcohol may be a conventional choice in the art. Examples of
the alcohol include, but are not limited to at least one of methanol, ethanol, n-propanol,
isopropanol, and n-butanol, etc.
[0031] Furthermore, the present invention further provides an in-reactor polyolefin alloy
obtained by the above-mentioned method.
[0032] Hereunder the present invention will be detailed in examples.
[0033] In the following examples and reference examples, the gel content in the in-reactor
polyolefin alloy is measured with the following method:
The in-reactor polyolefin alloy is dried in an vacuum drying oven at 50°C till the
weight doesn't change any more, the dry polymer is weighed and the weight is denoted
as W
1, then the dried in-reactor polyolefin alloy is dissolved in dimethyl benzene at 135°C
while the solution is oscillated till the in-reactor polyolefin alloy is dissolved
extensively, the solution is filtered through a 200-mesh stainless steel screen, the
undissolved polymer left on the stainless steel screen is collected, and then dried
in a vacuum drying oven at 100°C for 4h, then the dry polymer is weighed and the weight
is denoted as W
2; then the gel content in the in-reactor polyolefin alloy is calculated with the following
formula:
Example 1
[0034] This example is provided to describe the method of preparing an in-reactor polyolefin
alloy provided in the present invention.
[0035] In a vacuum state, 500g liquid propylene monomer is loaded into a reactor, then 0.25mol
triethyl aluminum, 20mg olefin polymerization catalyst (MgCl
2/TiCl
4/BMMF, wherein BMMF is an internal electron donor 9,9-dimethoxy fluorene, and the
mass ratio of MgCl
2 to TiCl
4 to BMMF is 80:12:8), and 0.2g hydrogen are charged in sequence at 30°C, and then
the reaction temperature is increased to 70 °C, and the mixture is held at the temperature
for 0.2h for reaction. Next, the residual propylene monomer in the reactor is discharged,
and the temperature in the reactor is decreased to 50°C; then 0.10mL di-(7-octenyl)
dichlorosilane is added, and a gas mixture of 20g ethylene and 60g propylene is charged
into the reactor, and the reaction temperature is controlled at 90 °C for 0.2h for
reaction; after the reaction is finished, acidified ethanol is added to terminate
the polymerization reaction, and then the product is washed with 50 °C deionized water
and 50°C ethanol for 3 times respectively; finally the product is vacuum-dried at
60°C; thus, an in-reactor polypropylene alloy is obtained. Measured in a detection
process, the concentration of di-(7-octenyl) dichlorosilane in the in-reactor polypropylene
alloy is 278ppm, the rubber phase in the in-reactor polypropylene alloy has a crosslinked
structure, and the gel content in the in-reactor polypropylene alloy is 50wt.%.
Comparative Example 1
[0036] This comparative example is provided to describe the method of preparing an reference
in-reactor polyolefin alloy.
[0037] The in-reactor polyolefin alloy is prepared by the method described in Example 1,
but no di-(7-octenyl) dichlorosilane is added; thus, a reference in-reactor polypropylene
alloy is obtained.
Comparative Example 2
[0038] This comparative example is provided to describe the method of preparing an reference
in-reactor polyolefin alloy.
[0039] The in-reactor polyolefin alloy is prepared by the method described in Example 1,
but the di-(7-octenyl) dichlorosilane is replaced with tetrachlorosilane in the same
volume; thus, a reference in-reactor polypropylene alloy is obtained.
Comparative Example 3
[0040] This comparative example is provided to describe the method of preparing an reference
in-reactor polyolefin alloy.
[0041] The in-reactor polyolefin alloy is prepared by the method described in Example 1,
but the di-(7-octenyl) dichlorosilane is replaced with tetramethoxysilane in the same
volume; thus, a reference in-reactor polypropylene alloy is obtained.
Example 2
[0042] This example is provided to describe the method of preparing an in-reactor polyolefin
alloy provided in the present invention.
[0043] In a vacuum state, 500g liquid propylene monomer is loaded into a reactor, then 0.25mol
triethyl aluminum, 20mg olefin polymerization catalyst (MgCl
2/TiCl
4/BMMF, wherein BMMF is an internal electron donor 9,9-dimethoxy fluorene, and the
mass ratio of MgCl
2 to TiCl
4 to BMMF is 80:15:5), and 0.2g hydrogen are charged in sequence at 30°C, and then
the reaction temperature is increased to 70 °C, and the mixture is held at the temperature
for 0.2h for reaction. Next, the residual propylene monomer in the reactor is discharged,
and the temperature in the reactor is decreased to 50 °C; then 0.05mL di-[2-(5-ethylidene-2-norbornene)
ethyl] dichlorosilane is added, and a gas mixture of 20g ethylene and 60g propylene
is charged into the reactor, and the reaction temperature is controlled at 90 °C for
0.5h for reaction; after the reaction is finished, acidified ethanol is added to terminate
the polymerization reaction, and then the product is washed with 90 °C deionized water
and 80°C ethanol for 3 times respectively; finally the product is vacuum-dried at
60°C; thus, an in-reactor polypropylene alloy is obtained. Measured in a detection
process, the concentration of di-[2-(5-ethylidene-2-norbornene) ethyl] dichlorosilane
in the in-reactor polypropylene alloy is 125ppm, the rubber phase in the in-reactor
polypropylene alloy has a crosslinked structure, and the gel content in the in-reactor
polypropylene alloy is 70wt.%.
Example 3
[0044] This example is provided to describe the method of preparing an in-reactor polyolefin
alloy provided in the present invention.
[0045] In a vacuum state, 500g liquid propylene monomer is loaded into a reactor, then 0.25mol
triethyl aluminum, 20mg olefin polymerization catalyst (MgCl
2/TiCl
4/BMMF, wherein, BMMF is an internal electron donor 9,9-dimethoxy fluorene, and the
mass ratio of MgCl
2 to TiCl
4 to BMMF is 78:12:10), and 0.2g hydrogen are charged in sequence at 30°C, and then
the reaction temperature is increased to 70 °C, and the mixture is held at the temperature
for 0.2h for reaction. Next, the residual propylene monomer in the reactor is discharged,
and the temperature in the reactor is decreased to 50°C; 0.1mL di-[2-(3-cyclohexenyl)
ethyl] dichlorosilane is added into the reactor, then a gas mixture of 20g ethylene
and 60g propylene is charged into the reactor, and the reaction temperature is controlled
at 90°C for 0.5h for further reaction; after the reaction is finished, an in-reactor
polypropylene alloy is obtained. Measured in a detection process, the concentration
of di-[2-(3-cyclohexenyl) ethyl] dichlorosilane in the in-reactor polypropylene alloy
is 210ppm, the rubber phase in the in-reactor polypropylene alloy has a crosslinked
structure, and the gel content in the in-reactor polypropylene alloy is 65wt.%.
Example 4
[0046] This example is provided to describe the method of preparing an in-reactor polyolefin
alloy provided in the present invention.
[0047] The in-reactor polyolefin alloy is prepared by the method described in Example 1,
but the di-(7-octenyl) dichlorosilane is replaced with 2-(dicyclopentadiene)ethylidene
trichlorosilane in the same volume; thus, an in-reactor polypropylene alloy is obtained.
Measured in a detection process, the concentration of 2-(dicyclopentadiene) ethylidene
trichlorosilane in the in-reactor polypropylene alloy is 142ppm, the rubber phase
in the in-reactor polypropylene alloy has a crosslinked structure, and the gel content
in the in-reactor polypropylene alloy is 45wt.%.
Example 5
[0048] This example is provided to describe the method of preparing an in-reactor polyolefin
alloy provided in the present invention.
[0049] The in-reactor polyolefin alloy is prepared by the method described in Example 1,
but the di-(7-octenyl) dichlorosilane is replaced with 7-octenyl dimethoxy chlorosilane
in the same volume; thus, an in-reactor polypropylene alloy is obtained. Measured
in a detection process, the concentration of 7-octenyl dimethoxy chlorosilane in the
in-reactor polypropylene alloy is 856ppm, the rubber phase in the in-reactor polypropylene
alloy has a branched or crosslinked structure, and the gel content in the in-reactor
polypropylene alloy is 20wt.%.
Example 6
[0050] This example is provided to describe the method of preparing an in-reactor polyolefin
alloy provided in the present invention.
[0051] In a vacuum state, 450g liquid propylene monomer is charged into a reactor, then
0.25mol triethyl aluminum and 18mg olefin polymerization catalyst (MgCl
2/TiCl
4/BMMF/rac-Me
2Si(2-Me-4-PhInd)
2ZrCl
2/aluminum methylate, wherein BMMF is an internal electron donor 9,9-dimethoxy fluorene,
rac- represents "racemized", Me is methyl, Ph is phenyl, Ind is indentyl, and the
mass ratio of MgCl
2 to TiCl
4 to BMMF to rac-Me
2Si(2-Me-4-PhInd)
2ZrCl
2 to aluminum methylate is 60:8:5:1:16) are added in sequence at 30°C, the reaction
temperature is controlled at 70°C, and the mixture is held at the temperature for
30min for polymerization reaction; after the polymerization is finished, the residual
propylene monomer in the reactor is discharged, and the temperature in the reactor
is decreased to 50°C; then 1.0mL allyltrichlorosilane is added into the reactor, and
a gas mixture of 20g ethylene and 60g propylene and 0.05g hydrogen are charged into
the reactor, the reaction temperature is controlled at 90 °C for 0.5h for further
reaction; after the reaction is finished, an in-reactor polypropylene alloy is obtained.
Measured in a detection process, the concentration of allyltrichlorosilane in the
in-reactor polypropylene alloy is 590ppm, the rubber phase in the in-reactor polypropylene
alloy has a crosslinked structure, and the gel content in the in-reactor polypropylene
alloy is 75wt.%.
Test Cases
[0052] The test cases are provided to describe the tests of the mechanical properties of
the in-reactor polyolefin alloy.
[0053] The impact strength is measured with the method specified in ASTM D256A, and the
result is shown in Table 1.
[0054] The tensile strength is measured with the method specified in ISO527-2-5A, and the
result is shown in Table 1.
Table 1
No. |
Gel content, mass% |
Impact strength, kJ/m2 |
Tensile breaking strength, MPa |
Example 1 |
50 |
55.0 |
13.0 |
Comparative Example 1 |
0 |
22.4 |
22.5 |
Comparative Example 2 |
0 |
18.6 |
25.4 |
Comparative Example 3 |
0 |
19.5 |
26.5 |
Example 2 |
70 |
59.0 |
10.1 |
Example 3 |
65 |
56.8 |
11.2 |
Example 4 |
45 |
50.0 |
14.5 |
Example 5 |
20 |
32.5 |
18.4 |
Example 6 |
75 |
50.6 |
9.8 |
[0055] It is seen from the above result: the in-reactor polyolefin alloy obtained by the
method provided in the present invention contains a highly crosslinked rubber phase,
and has higher impact toughness and lower tensile breaking strength. It is seen from
the comparison between Example 1 and Example 4-5: if the R
1 in the organosilane is a C
2-C
20 alkyl group and a terminal of R
1 has an α-double bond, a norbornene group, a cycloolefin group or a dicyclopentadiene
group, X is a halogen element, R
2 is a C
1-C
10 linear chain, branched chain or isomerized alkyl group, m is 2 or 3, n is 1 or 2,
k is 0, and m+n+k=4, the rubber phase in the obtained in-reactor polyolefin alloy
is crosslinked to a higher degree, and the in-reactor polyolefin alloy has higher
impact strength and lower tensile breaking strength. It is seen from the comparison
between Example 1 and Comparative Example 2-3: the organosilane provided in the present
invention behaves differently from silicon tetrahlaide and tetraalkoxysilane in the
olefin polymerization reaction process, and the in-reactor polyolefin alloy obtained
with the organosilane provided in the present invention has higher impact toughness
and lower tensile breaking strength.
[0056] While some preferred embodiments of the present invention are described above, the
present invention is not limited to the details in those embodiments. Those skilled
in the art can make modifications and variations to the technical scheme of the present
invention, without departing from the spirit of the present invention. However, all
these modifications and variations shall be deemed as falling into the scope of protection
of the present invention.
[0057] In addition, it should be noted that the specific technical features described in
above embodiments can be combined in any appropriate form, provided that there is
no conflict. To avoid unnecessary repetition, the possible combinations are not described
specifically in the present invention.
[0058] Moreover, different embodiments of the present invention can be combined freely as
required, as long as the combinations don't deviate from the ideal and spirit of the
present invention. However, such combinations shall also be deemed as falling into
the scope disclosed in the present invention.
1. A use of organosilane in preparation of an in-reactor polyolefin alloy, wherein the
organosilane is represented by a general formula R1mSiXn(OR2)k, wherein R1 is a C2-C20 alkyl group and a terminal of R1 has an α-olefin double bond, a norbornene group, or a dicyclopentadiene group, X
is a halogen element, R2 is a C1-C20 linear chain, branched chain or isomerized alkyl group, m is an integer within a
range of 1-3, n is an integer within a range of 1-3, k is an integer within a range
of 0-2, and m+n+k=4.
2. The use according to claim 1, wherein R1 is a C2-C20 alkyl group and a terminal of R1 has an α-olefin double bond, a norbornene group, a cycloolefin group or a dicyclopentadiene
group, X is a halogen element, R2 is a C1-C10 linear chain, branched chain or isomerized alkyl group, m is 2 or 3, n is 1 or 2,
k is 0, and m+n+k=4.
3. The use according to claim 2, wherein the organosilane is at least one of 7-octenyl
allyl dichlorosilane, 7-octenyl vinyl dichlorosilane, 5-hexenyl allyl dichlorosilane,
7-octenyl di-(allyl) chlorosilane, di-(7-octenyl) allyl chlorosilane, di-(7-octenyl)
dichlorosilane, triallyl chlorosilane, di-(allyl) dichlorosilane, 2-(5-ethylidene-2-norbornene)
ethyl allyl dichlorosilane, di-[2-(5-ethylidene-2-norbornene) ethyl] dichlorosilane,
di-[2-(3-cyclohexenyl) ethyl] dichlorosilane, 2-(dicyclopentadiene) ethylidene allyl
dichlorosilane, and di-[2-(dicyclopentadiene) ethylidene] dichlorosilane.
4. A method of preparing an in-reactor polyolefin alloy comprising: conducting the first
polymerization reaction of the first olefin monomer in the presence of a catalyst,
and then charging the second olefin monomer into the polymerization reaction system
to perform the second polymerization reaction, wherein the first olefin monomer is
different from the second olefin monomer, the first polymerization reaction and/or
the second polymerization reaction are/is executed in the presence of an organosilane
represented by a general formula R1mSiXn(OR2)k, wherein R1 is a C2-C20 alkyl group and a terminal of R1 has an α-olefin double bond, a norbornene group, a cycloolefin group or a dicyclopentadiene
group, X is a halogen element, R2 is a C1-C20 linear chain, branched chain or isomerized alkyl group, m is an integer within a
range of 1-3, n is an integer within a range of 1-3, k is an integer within a range
of 0-2, and m+n+k=4.
5. The method according to claim 4, wherein R1 is a C2-C20 alkyl group and a terminal of R1 has an α-olefin double bond, a norbornene group, a cycloolefin group or a dicyclopentadiene
group, X is a halogen element, R2 is a C1-C10 linear chain, branched chain or isomerized alkyl group, m is 2 or 3, n is 1 or 2,
k is 0, and m+n+k=4.
6. The method according to claim 5, wherein the organosilane is at least one of 7-octenyl
allyl dichlorosilane, 7-octenyl vinyl dichlorosilane, 5-hexenyl allyl dichlorosilane,
7-octenyl di-(allyl) chlorosilane, di-(7-octenyl) allyl chlorosilane, di-(7-octenyl)
dichlorosilane, triallyl chlorosilane, di-(allyl) dichlorosilane, 2-(5-ethylidene-2-norbornene)
ethyl allyl dichlorosilane, di-[2-(5-ethylidene-2-norbornene) ethyl] dichlorosilane,
di-[2-(3-cyclohexenyl) ethyl] dichlorosilane, 2-(dicyclopentadiene) ethylidene allyl
dichlorosilane, and di-[2-(dicyclopentadiene) ethylidene] dichlorosilane.
7. The method according to any one of claims 4-6, wherein in relation to 100pbw total
dose of the first olefin monomer and the second olefin monomer, the total dose of
the organosilane is 0.0001-20pbw.
8. The method according to any one of claims 4-7, wherein the first polymerization reaction
is executed without the presence of the organosilane, while the second polymerization
reaction is executed in the presence of the organosilane.
9. The method according to any one of claims 4-8, wherein the catalyst is at least one
of Ziegler-Natta catalyst, metallocene catalyst, and non-metallocene catalyst;
preferably, the first olefin monomer is propylene, and the second olefin monomer is
a mixture of ethylene and α-olefin;
preferably, the conditions of the first polymerization reaction include: reaction
temperature in the range of 30-90°C, reaction time in the range of 0.05-10h; the conditions
of the second polymerization reaction include: reaction temperature in the range of
60-120°C, reaction time in the range of 0.1-10h.
10. The method according to any one of claims 4-9 further comprising: washing the product
obtained by the second olefin polymerization reaction with water and/or alcohol at
20-120°C, after the second olefin polymerization reaction is finished.
11. An in-reactor polyolefin alloy prepared by the method according to any one of claims
4-10.